She revealed earlier this week that she knew her best friend Drew Barrymore was getting married even before she did.And Cameron Diaz's close bond with her fellow actress was clear when she accompanied Drew to her final wedding dress fitting today.The pair, who have known each other since they were teenagers, were spotted leaving the Chanel store in Beverly Hills with coy smiles on their faces.Drew and fiancé Wil Kopelman, who picked up his attire in a garment bag, are due to tie the knot this weekend at her estate in Montecito, California - and Cameron is expected to be a bridesmaid at the ceremony.The best pals were dressed casually as they left the fitting, with Cameron in a white T-shirt and aquamarine skinny jeans while the bride-to-be sported a baggy black top and boyfriend jeans, along with tan ankle boots.

Close bond: Cameron is expected to be a bridesmaid at the ceremony, due to take place this weekend

Cameron revealed to InStyle magazine that Drew's fiancé sought her out before he popped the question to ask for her blessing to the union and said: 'I knew Drew was getting married before she did!'

Keeping coy: The pair tried to stifle smiles as they left the Chanel store in Beverly Hills

And clearly she did give her blessing as Drew and Wil are now betrothed and also expecting their first baby together.Babies seem to be the hot subject at the moment for Cameron, who is currently starring in the new smash-hit movie What to Expect When You’re Expecting.Cameron plays Jules, an aspiring singer and a host to a weight loss fitness show who then has to face a surprise pregnancy and battle with boyfriend Evan, played by Glee's Matthew Morrison, on how to raise their child.

Groom to be: Drew's fiance Wil Kopelman was seen collecting his wedding attire from the store in a garment bag

Friends for life: Cameron, who has been pals with Drew since they were teenagers, knew Drew was getting married even before she did

Three years ago, the actress hinted that she didn't want to have children when she said: 'I think women are afraid to say that they don't want children because they're going to get shunned.'I have more girlfriends who don't have kids than those that do. And honestly? We don't need any more kids. We have plenty of people on this planet.'But she seems to have had a change of heart as she spoke to the magazine, and posed for a sexy shoot for the publication, about children.

Best friend: Drew Barrymore and her fiancé Wil Kopelman, who asked Cameron's blessing, arrive at their engagement party earlier this month

She said: 'Society definitely puts pressure on women to make them think their lives should go a certain way.'I’ve never said I don’t want children - I just haven’t had children yet. I don’t know what’s going to happen in my life! 'I could end up adopting children. I could end up with a partner who already has children. Who knows? I’m not trying to fit into anyone’s box about how I should be. I just fit in my own box.'

What To Expect When You're Expecting: Cameron stars as a new mum in the movie alongside Glee's Matthew Morrison